题目

— _____ —Go along this road to the end. A.What are we doing at the supermarket? B.Who can get to the supermarket? C.How can I get to the supermarket?     答案：C已知：如图，AD∥OB，OC平分∠AOB，P是OC上一点，过点P作直线MN，分别交AD、OB于点M和N，且MP=NP．求证：点P到AO和AD的距离相等．